87×21+0.25×21+0.5这道题的简便方法?

2024-10-30 12:21:36
推荐回答(1个)
回答1:

87*21+0.25*21+0.5
=21*(87+0.25)+0.5
=81*87.25+0.5
=7067.25+0.5
=7067.75